[GHC] #15181: Levity Polymorphic type signatures in GHC.Prim

[GHC]

#15181: Levity Polymorphic type signatures in GHC.Prim
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        Reporter:  andrewthad        |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.2
      Resolution:  duplicate         |             Keywords:
                                     |  LevityPolymorphism
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11786            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 I'm not intimately familiar with the specifics, but I do know that
 `GHC.Prim` (and other code which adds magical properties to functions
 defined therein) is generated through the
 [http://git.haskell.org/ghc.git/tree/a32c8f7514c8192fa064537fb93d5a5c224991a0:/utils/genprimopcode
 genprimopcode] utility. `genprimopcode` has a convention that any type
 variable named `o` is levity polymorphic, so that's why `a -> o` gets a
 wired-in levity polymorphic type.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15181#comment:7>
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